High-tension barrier-layer rectification unit for installation in the high-tension generator of an X-ray apparatus



J. SEIDEL ETAL 2,844,771 HIGH-TENSION BARRIER-LAYER RECTIFICATION UNIT FOR 'July 22, 1958 INSTALLATION IN THE HIGH-TENSION GENERATOR OF AN X-RAY APPARATUS Filed Jan. 15,l957 I A, A Z Z 3 2 7 WI a e i, 6

F19 7 idea Z02 5 HIGH-TENSION BARRIER-LAYER RECTIFICA- TION UNIT FOR INSTALLATION IN THE HIGH-TENSIUN GENERATOR OF AN X -RAY APPARATUS Johannes Seidel and Lothar Meier, Erlangen, Germany,

assignors to Siemens-Reiniger-Werke Aktiengesellschaft, Erlangen, Germany This invention relates to a high-tension barrier-layer rectification unit for inserting in the high-tension part of an X-ray apparatus in place of the'rectifying valves. Such a unit comprises several rectifier columns each consisting of a round porcelain tube, in which the quadratic rectifier elements are stacked immediately on top of one another in the longitudinal direction of the tube in a quadratic bore. Several such tubes are placed with their longitudinal axes next to one another and with each end fitted in a socket they are combined together to form the high-tension barrier-layer rectification unit. The rectifier columns placed next to each other are electrically connected in series with one another in the manner that the one ends of the first and second columns of the unit-located on the same side of the unitand the other ends of the second and third columns, and the one ends of the third and fourth columns of the unit, etc. are connected to each other.

This invention concerns deficiencies of a unit as outlined above. Such a deficiency is the rotation of the tubes in their sockets. Thereby, the distance between opposing edges of the rectifying elements of adjacent columns, and thus the dielectric strength of the unit is variable. In one case, the quadratic elements of adjacent columns are situated so that their side walls are parallel to each other, and in the other case, with their edges facing each toher. The latter position is less favorable as concerns withstanding the potentials, when the distance between the columns is the same. The necessity to employ separate sockets which hold the tubes mechanically at their ends is also a drawback. Such sockets must be used since the round porcelain tubes cannot be provided with exterior holding means in a simple manner. If said holders were fixed to the tubes during the molding process, the manufacturing costs for the tubes would be rather high.

Another deficiency resides in the design of the tubes, which have closed walls. Proper cooling of the rectifying elements cannot be obtained in this manner and it is, for instance, not easily possible to tap electrically the center of a column, which is frequently necessary on account of different wiring systems.

According to the invention, the rectifying columns are housed in containers of insulating plastic material of which the external cross-section is also rectangular, the containers being provided with longitudinally extending slots so that a substantial portion of the edges of the rectifying elements is uncovered; the containers being held by a carrier of insulating material which is common thereto.

The longitudinal slots allow the cooling medium to reach the rectifying elements readily. The design of the insulating containers makes it possible to drill in simple manner holes in their ends for their mechanical holders. On account of the exteriorly rectangular cross-section of the containers, they can be easily put together and are secured against rotation.

ates Patent ice The various objects and features of the invention will Fig. 5 is an elevation illustrating a number of the details shown in Fig. 3, connected to a plate;

Fig. 6 indicates a first example of electrically connecting the components of a unit; and

Fig. 7 illustrates a second example of electrically conmeeting the components of a unit.

Fig. 1 shows a single container of the unit according to i the invention. The container consists of a tube of pressed insulating material 1, which is closed at both ends, has an exterior and interior quadratic cross-section, and is laterally provided with a broad longitudinal slot 2 and narrow longitudinal slots 3, which are clearly indicated in the cross-section shown in Fig. 2. Slot 2 in Fig. 1 ends at the upper recess 4, which serves to facilitate insertion of the rectifying elements 5. The rectifying elements 5 are held by the pressure of spring 6'.

The rectifying column and the spring 6 are included between two contact bodies 7, 8. The connection from these contact bodies to the outside is made via lateral bores 9, 10. The slots 2, 3 are provided to ensure that the cooling medium can readily reach the rectifiers. Moreover, particularly the broad slot 2 allows to tap the rectifying column electrically in a simple manner, since a contact plate can be inserted at any place between two elements of the rectifying column which is held by spring pressure.

Another container, which can be easier manufactured, is shown in Fig. 3 where the longitudinal walls consist of two U-rails 11, 12, which, after the elements 5 have been stacked in and the spring 6 has been inserted, are held together at the upper and lower end so that a container of quadratic cross-section and with longitudinal slots is formed. The rails 11, 12 can be easily manufactured by extrusion. The two rails 11, 12 are spaced from each other with the aid of metal blocks 13, 14, the crosssection of which corresponds to that of the rectifying elements, to which the rails 11, 12 are fastened on both sides, after the elements 5 and the spring 6 have been inserted, by means of hollow rivets 19, 20, that are passed through the bores 15, 16 on the metal blocks 13, 14, and the bores 17, 18 on the rails 11, 12.

The hollow rivets 19, 20 also serveto assemble the individual containers to form one unit. The required stability of the containers is suitably achieved with the aid of an insulating plate 21 of plastic material as shown in Fig. 4, to which the containers are fixed at a short distance from the plate 21 by means of hollow rivets 22, 23 which are passed through the hollow rivets 19, 20. According to this invention, an insulating frame may be employed instead of the insulating plate 21.

The insulating part, however, which carries the columns, must be of suflicient inherent torsional stability. The containers are spaced from each other so that the cooling medium can readily reach the rectifying elements 5.

The rectifying columns are electrically connected to each other by means of non-flexible wires 24, the ends of which are inserted into the hollow rivets 22, 23 and soldered thereto at 25, 26. The wires 24 are, according to the rear view of the plate 21 as shown in Fig. 5, equally spaced and arranged so that maximum field strength is not produced at any place. In order to suppress leakage currents on the surface of the plate, the wires 24 do not touch the plate 21 and the plate 21 is provided on its bottom and top sides with slot-shaped cutouts 27 extending between the holes for the leads.

The electrical connection between the rectifying columns as shown in Fig. 5 where the column ends situated on the same side of the unit are connected with the ends of adjacent columns on the other side of the unit (see Fig. 6)provides the advantage that the operational difierence in electrical potential across opposite points of adjacent containers cannot exceed the value which corresponds with the inverse voltage of one rectifying column. With the usual method-of connection employed in the previously mentioned high-tension barrier-layer rectification unit, where successive rectifying columns are connected at their ends located on the same side (see Fig. 7), is is possible that a potential difference of twice the inverse voltage of one rectifying column occurs in operation across such column ends that are not connected with each other.

Changes may be made within the scope and spirit of the appended claims.

We claim:

l. A high-tension barrier-layer rectification unit for insertion in the high-tension part of an X-ray apparatus, comprising a plurality of rod-shaped insulating containers, so arranged that their longitudinal axes are situatednext to each other, with quadratic rectifying elements stacked along in the longitudinal direction of the containers, the rectifying columns being housed in containers of pressed insulating material of which the exterior cross section is also quadratic, the containers being provided with slots in their longitudinal direction so that 'asubstantial portion of the edge surface of the rectifying elements is exposed and the containers being held by insulating carrier which is common thereto.

2. A high-tension barrier-layer rectification'unit according to claim 1, of which the containers are formed by two U-rails each whose legs confront each other and which are connected at both of theirends by one member each.

3. A high-tension barrier-layer rectification unit according to claim 2, with the connection members for the two U-rails being of the hollow body type.

4. A high-tension barrier-layer rectification unit according to claim 3, with a'metal spacer arranged between the two U-rails at every end, both spacers being electrically connected to the rectifying column, wherein a hollow rivet links the U-rails and the spacer.

5. A high-tension barrier-layer rectification unit according to claim 4, with an insulating carrier common to all containers, which supports every container separately by means for fastening members that are passed through the hollow rivet.

6. A high-tension barrier-layer rectification unit according to claim 5, with hollow rivets functioning as fastening members, and with the electrical connection leads between the columns being inserted into the hollow fastening rivets.

References Cited in the file of this patent UNITED STATES PATENTS 2,484,245 Pendleton et-al. Oct. 11, 1 949 2;5 6 2,Q43- Lamm et al. July 24, -1 2,750,540 Waldknotter et a1 June 12, 1956 

